Iran said it was now capable of raising uranium enrichment past the 20 per cent level and had launched advanced centrifuge machines in further breaches of commitments to limit its nuclear activity under a crumbling deal with world powers.
Forty such centrifuges were now operational, said nuclear agency spokesman Behruz Kamalvandi.
He added Tehran could now exceed the 20pc level, a significant leap towards the critical 90pc, “but right now there is no need for that”.
Enriched uranium can be used to make reactor fuel but also nuclear weapons.
Iran stopped abiding by two commitments in July in response to sanctions the US reinstated when it abandoned the deal.
President Donald Trump wants to force Iran to negotiate a new agreement that would place indefinite curbs on its nuclear programme and also halt its development of ballistic missiles. But Iran has so far refused.